Prevalence and trends in tobacco use among adolescents aged 13-15 years in 143 countries, 1999-2018: findings from the Global Youth Tobacco Surveys.

BACKGROUND: Tobacco use is a leading preventable cause of morbidity and mortality worldwide. Little is known about recent prevalence and trends in tobacco use among adolescents globally. We aimed to assess the recent global prevalence of tobacco use in young adolescents and the secular trends in prevalence between 1999 and 2018. METHODS: We used the most recent Global Youth Tobacco Surveys data on adolescents aged 13-15 years from 143 countries or territories that had done at least one survey between Jan 1, 2010, and Dec 31, 2018, to assess the recent prevalence of tobacco use; and data from 140 countries that had done two or more surveys between Jan 1, 1999, and Dec 31, 2018, to assess the trends in the prevalence of tobacco use. FINDINGS: 530 234 adolescents were included from the 143 countries that had done at least one survey between 2010 and 2018. 1 192 312 adolescents were included from the 140 countries that had done two or more surveys between 1999 and 2018. The most recent global prevalence of cigarette smoking was 11·3% (95% CI 10·3-12·3) in boys and 6·1% (5·6-6·6) in girls, based on cigarette smoking on at least 1 day during the past 30 days, 6·0% (5·5-6·6) and 2·6% (2·4-2·9) based on smoking on at least 3 days, and 4·2% (3·8-4·6) and 1·6% (1·4-1·8) based on smoking on at least 6 days. The most recent prevalence of the use of tobacco products other than cigarettes (eg, chewing tobacco, snuff, dip, cigars, cigarillos, pipe, electronic cigarettes) on at least 1 day during the past 30 days was 11·2% (9·9-12·6) in boys and 7·0% (6·4-7·7) in girls. The most recent prevalence of any tobacco use on at least 1 day during the past 30 days was 17·9% (16·1-19·6) in boys and 11·5% (10·5-12·4) in girls. The prevalence of cigarette smoking on at least 1 day during the past 30 days decreased between the first and last surveys in 80 (57·1%) of 140 countries, was unchanged in 39 countries (27·9%), and increased in 21 countries (15·0%). However, the prevalence of the use of tobacco products other than cigarettes was unchanged or increased in 81 (59·1%) of 137 countries. INTERPRETATION: The global prevalence of tobacco use among adolescents aged 13-15 years was substantial. Although the prevalence of cigarette smoking decreased over time in the majority of countries, the prevalence of the use of other tobacco products increased or did not change in the majority of countries during the past two decades. These findings re-emphasise the need to strengthen tobacco control efforts among young adolescents globally. FUNDING: Shandong University.

24-Year trends in educational inequalities in adult smoking prevalence in the context of a national tobacco control program: The case of Brazil.

Brazil was a low and middle-income country (LMIC) in the late-1980s when it implemented a robust national tobacco-control program (NTCP) amidst rapid gains in national incomes and gender equality. We assessed changes in smoking prevalence between 1989 and 2013 by education level and related these changes to trends in educational inequalities in smoking. Data were from four nationally representative cross-sectional surveys (1989, n = 25,298; 2003 n = 3845; 2008 n = 28,938; 2013 n = 47,440, ages 25-69 years). We estimated absolute (slope index of inequality, SII) and relative (relative index of inequality, RII) educational inequalities in smoking prevalence, separately for males and females. Additional analyses stratified by birth-cohort to assess generational differences. Smoking declined significantly between 1989 and 2013 in all education groups but declines among females were steeper in higher-educated groups. Consequently, both absolute and relative educational inequalities in female smoking widened threefold between 1989 and 2013 (RII: 1.31 to 3.60, SII: 5.3 to 15.0), but absolute inequalities in female smoking widened mainly until 2003 (SII: 15.8). Conversely, among males, declines were steeper in higher-educated groups only in relative terms. Thus, relative educational inequalities in male smoking widened between 1989 and 2013 (RII: 1.58 to 3.19) but mainly until 2008 (3.22), whereas absolute equalities in male smoking were unchanged over the 24-year period (1989: 21.1 vs. 2013: 23.2). Younger-cohorts (born ≥1965) had wider relative inequalities in smoking vs. older-cohorts at comparable ages, particularly in the youngest female-cohorts (born 1979-1988). Our results suggest that younger lower-SES groups, especially females, may be particularly vulnerable to differentially higher smoking uptake in LMICs that implement population tobacco-control efforts amidst rapid societal gains.

Does Interest in Smoking Affect Youth Selection of Pro-smoking Videos? A Selective Exposure Experiment.

BACKGROUND: Many pro-smoking videos on YouTube reach view counts in the hundreds of thousands and more. Yet, there is limited information on who is viewing these potentially misleading videos. This study attempts to understand the viewership of online pro-smoking videos to examine if youth at high risk for smoking are more likely to watch these videos. METHODS: We conducted a selective exposure experiment with a national sample of youths (ages 15-21 years; n = 614) to identify characteristics that make individuals more likely to select pro-smoking videos. During a 10-min browsing session, participants were given a set of 16 videos (eight smoking and eight nonsmoking) and were asked to view video(s) of their choice. Exposure to videos was unobtrusively logged. View count was manipulated such that smoking videos had either high or low views. RESULTS: Behavioral data revealed that youth with higher interest in smoking were more likely to select and spend more time watching pro-smoking videos than youth with lower interest in smoking. The view count manipulation did not affect selection patterns. However, exposure to high view count smoking videos was associated with more positive attitudes toward smoking. CONCLUSIONS: The findings of this study call into question the existence and prominence of pro-smoking videos on YouTube and bring to attention the need for regulatory or monitoring efforts of such content. IMPLICATIONS: Given the presence and prevalence of misleading pro-smoking videos online, this is the first study to ask the practical and important question of who is viewing these videos. Using behavioral data, we are able to demonstrate that youth who are high at risk for smoking are more susceptible to select and spend more time viewing pro-smoking videos than youth who are low at risk for smoking. Findings also show that when pro-smoking videos appear to be "popular," they affect attitudes toward smoking. Our findings provide policy implications regarding regulation of smoking promotion videos online.

Comparative analysis of COPD associated with tobacco smoking, biomass smoke exposure or both.

BACKGROUND: Exposure to noxious gases and particles contained in both tobacco smoking (TS) and biomass smoke (BS) are well recognized environmental risk factors for chronic obstructive pulmonary disease (COPD). COPD is characterized by an abnormal inflammatory response, both in the pulmonary and systemic compartments. The differential effects of TS, BS or their combined exposure have not been well characterized yet. This study sought to compare the lung function characteristics and systemic inflammatory response in COPD patients exposed to TS, BS or their combination. METHODS: Sociodemographic, clinical and lung functional parameters were compared across 49 COPD patients with a history of smoking and no BS exposure (TS COPD), 31 never-smoker COPD patients with BS exposure (BS COPD), 46 COPD patients with a combined exposure (TS + BS COPD) and 52 healthy controls (HC) who have never been exposed neither to TS or BS. Blood cell counts, C-reactive protein (CRP), fibrinogen and immunoglobulin E (IgE) levels were quantified in all four groups. RESULTS: TS + BS COPD patients exhibited significantly lower oxygen saturation than the rest of groups (p < 0.01). Spirometry and diffusing capacity were significantly higher in BS than in TS or TS + BS patients. CRP levels were significantly higher in TS COPD patients than in BS COPD group (p < 0.05), whereas fibrinogen was raised in COPD patients with a history of smoking (TS and TS + BS) when compared to control subjects (p < 0.01). Finally, COPD patients with BS exposure (BS and BS + TS groups) showed higher IgE levels than TS and HC (p < 0.05). CONCLUSIONS: There are significant physiological and inflammatory differences between COPD patients with TS, BS and TS + BS exposures. The latter had worse blood oxygenation, whereas the raised levels of IgE in BS exposed patients suggests a differential Th2 systemic inflammatory pattern triggered by this pollutant.

A Survey of Nicotine Yields in Small Cigar Smoke: Influence of Cigar Design and Smoking Regimens.

Introduction: Although the popularity of small cigar brands that resemble cigarettes, including both little cigars (LC) and filtered cigars (FC), has been on the rise, little is known about the delivery of nicotine from these products. Our objective was to determine the nicotine yields of small cigars in comparison to cigarettes. Methods: Nicotine yields from LC, FC, and 3R4F and 1R6F research cigarettes were determined from mainstream smoke generated on a smoking machine under the International Organization of Standardization (ISO) and Canadian Intense (CI) methods. Market characteristics (price and package label) and physical features (filter ventilation, product weight and filter weight, product length, and diameter) were also determined for eight brands of small cigars. Results: Nicotine yields in small cigars averaged 1.24 and 3.49 mg/unit on ISO and CI regimens, respectively, compared with 0.73 and 2.35 mg/unit, respectively, for the research cigarettes. Nicotine yields per puff were similar between small cigars and cigarettes. We also found that FC did not differ from LC in nicotine yields. FC and LC differ from each other in many physical design features (unit weight, filter weight, and filter length), but are similar in others (unit length, diameter, and filter ventilation). Conclusions: Nicotine delivery from small cigars is similar to or greater than that from cigarettes. Thus, for future research and regulatory purposes, standard definitions need to be developed for small cigars, and FC and LC should be evaluated as separate entities. Implications: Small cigars are similar to cigarettes in their design and use. Although nicotine yields per puff were similar between products, small cigars delivered substantially higher amounts of nicotine per unit than cigarettes. These findings support the growing body of evidence to justify regulating all small cigars, including LC and FC in a similar fashion as cigarettes.